<?php
abstract class AbstractClass {
    abstract public function abstractFoo();
}

abstract class AbstractClass2 {
    abstract public function abstractFoo();
    abstract public function abstractBar();
}

class ExtendingClass1 extends AbstractClass {

}

class ExtendingClass2 extends AbstractClass {
}

class ExtendingClass3 extends AbstractClass
{
}

class ExtendingClass4 extends AbstractClass {

    private $foo = array(
        "foo1",
        "foo2",
        "foo3"
    );
}

class ExtendingClass5 extends AbstractClass2 {

    public function abstractFoo() {
    }

    public function abstractFoo2() {
    }
}

interface InterfaceName {
    public function abstractBar();
}

class ImplementingClass implements InterfaceName {

}
